High-sensitivity detection of trace metal impurities in aluminum alloys using CF-LIBS and CC-LIBS for industrial and environmental applications

In this work, trace elements in an aluminum matrix were quantitatively analyzed using Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) and Conventional Calibration Laser-Induced Breakdown Spectroscopy (CC-LIBS). When aluminum was used as the basis metal, impurities such as Copper (Cu), Zinc (Zn), Tin (Sn), Silicon (Si), and Lead (Pb) were added, and their distinctive emission lines were examined by a Q-switched Nd: YAG laser operating at 532 nm with 5 ns pulse width. The Al 394.4 nm line was used to standardize the intensities of the Cu, Zn, Sn, Si, and Pb spectral lines to improve accuracy and reduce experimental errors. The limit of detection (LOD) for each element was determined using calibration curves; the computed values for Cu, Zn, Sn, Si, Al, and Pb were 3.27, 4.5, 2.98, 4.46, 0.03, and 3.06 ppm, respectively. Additionally, the LODs for Al, Si, and Sn demonstrated enhancement over earlier reported values, while those for Pb, Cu, and Zn stayed identical, confirming the accuracy of our findings. Plasma variables were assessed using the Boltzmann plot technique, which used aluminum spectral lines to determine plasma temperature. The great sensitivity and accuracy of CF-LIBS and CC-LIBS revealed in this work make them ideal for metallurgical and alloy inspection, which ensures the purity and composition of aluminum-based products in the automotive, aerospace, and construction sectors. Furthermore, these approaches offer a quick and dependable way for aluminum recycling and trash management, facilitating the effective sorting and purification of metallic garbage. The capacity to identify harmful trace metal pollutants, such as Pb and Zn, has important implications for environmental monitoring, especially in businesses that employ aluminum in food packaging, medical equipment, and consumer electronics.